TOTP code generator

Generate the 6 or 8 digit 2FA code for a secret, and check a code you were given. Everything stays in the tab.

Base32 secret (the string your authenticator app was given)

Digits

Period (seconds)

Check offset (steps)

Current code

Verify a code

TOTP is HMAC-SHA1 over the time step, base32 secret, 30 second period by default (RFC 6238). A code is valid for the whole step, so a code generated at the very end of one can be rejected by a server whose clock is slightly ahead — that is what the check offset is for.